Endoscopically managed giant frontoethmoidal osteoma with orbital extension.

A patient in his 20s presented with a change in the appearance of his left eye with evidence of relative afferent pupillary defect. Imaging revealed a giant frontoethmoidal osteoma, a benign sinonasal tumour, invading three-quarters of the orbit. Multidisciplinary discussion involving opthalmology, maxillofacial surgery, neurosurgery and otolaryngology resulted in the decision to attempt entirely endoscopic excision of this lesion, which was performed with successful outcomes. This case demonstrates how a sinonasal osteoma should be considered in the differential diagnosis for a patient presenting with proptosis or other eye signs suggestive of compression of the orbital compartment. This case report and literature review highlights the possibility of managing giant sinonasal osteomas with orbital extension through a completely endoscopic approach.

[Based on CT imaging, surgical approach selection for frontal and ethmoid sinus osteoma].

Objective:To investigate the criteria for selecting surgical approaches for frontal and ethmoid sinus osteomas of different locations and sizes on CT imaging. Methods:Using sagittal and coronal CT images, the following lines were delineated: the F-line（a horizontal line passing nasofrontal beak）, the M-line（a vertical line passing paries medialis orbitae）, and the P-line（a vertical line passing the center of the pupil）. Classification of frontal and ethmoid sinus osteomas was based on their relationship with these lines. Appropriate surgical approaches were selected, including pure endoscopic approaches, endoscopic combined with eyebrow incision approach, and endoscopic combined with coronal incision approach. This method was applied to a single center at the Third Affiliated Hospital of Sun Yat-sen University for endoscopic resection of frontal and ethmoid sinus osteoma. Case Data: Sixteen cases of ethmoid sinus osteomas were treated from January 2020 to September 2023. Among these cases, there were 9 males and 7 females, with ages ranging from 18 to 69 years, and a median age of 48 years. Results:Thirteen cases underwent pure endoscopic resection of the osteoma, while in three cases, a combined approach was utilized. Among the combined approach cases, two exceeded both the M-line and the F-line but did not cross the P-line; therefore, they underwent endoscopic combined with eyebrow incision approach. One case exceeded all three lines and thus underwent endoscopic combined with coronal incision. In all cases, complete resection of the osteoma was achieved as per preoperative planning, and none of the patients experienced significant postoperative complications. Conclusion:For frontal and ethmoid sinus osteomas, it is advisable to perform a thorough preoperative radiological assessment. Based on the size of the osteoma and its relationship to the three lines, an appropriate surgical approach should be chosen to optimize the diagnostic and treatment plan.

Computed Tomography Evaluation of Frontal Sinus Volume in Migraine Patients.

This study aimed to assess the frontal sinus volume (FSV) on computed tomography (CT) scans in migraine patients. Cranial and paranasal CT images from 75 migraine patients (mean age: 39.14±13.63 y) and 23 control cases (mean age: 38.78±13.32 y) were analyzed retrospectively. Three-dimensionally reconstructed images of frontal sinuses were generated. Total FSV, anterolateral, and transverse diameters of the head were measured. The presence/absence and nature of supraorbital foramen and notches were evaluated. The total FSV was 8.02±5.97 cm 3 in the migraine group and 8.38±4.83 cm 3 in the control group, with no significant differences between them. Mean FSV values showed no statistically significant difference between females (7.79±5.85 cm 3 ) and males (9.12±6.66 cm 3 ) within and between the groups. Single notch was the most observed structure in both groups, with bilateral presence being the most common. Double foramen and notch were observed only in the migraine group, and the coexistence of both structures was higher in the migraine patients than in controls. There was no statistical difference in FSV between migraine and control groups, nor based on sex. Overall, the frontal region anatomy, particularly the exit locations of the supraorbital or supratrochlear foramen/notches, may be influenced by hyperplasia/hypoplasia of FSV. Therefore, assessing FSV using CT may be crucial for surgical planning in migraine patients undergoing open or endoscopic approaches to the frontal region.

Automatic segmentation and classification of frontal sinuses for sex determination from CBCT scans using a two-stage anatomy-guided attention network.

Sex determination is essential for identifying unidentified individuals, particularly in forensic contexts. Traditional methods for sex determination involve manual measurements of skeletal features on CBCT scans. However, these manual measurements are labor-intensive, time-consuming, and error-prone. The purpose of this study was to automatically and accurately determine sex on a CBCT scan using a two-stage anatomy-guided attention network (SDetNet). SDetNet consisted of a 2D frontal sinus segmentation network (FSNet) and a 3D anatomy-guided attention network (SDNet). FSNet segmented frontal sinus regions in the CBCT images and extracted regions of interest (ROIs) near them. Then, the ROIs were fed into SDNet to predict sex accurately. To improve sex determination performance, we proposed multi-channel inputs (MSIs) and an anatomy-guided attention module (AGAM), which encouraged SDetNet to learn differences in the anatomical context of the frontal sinus between males and females. SDetNet showed superior sex determination performance in the area under the receiver operating characteristic curve, accuracy, Brier score, and specificity compared with the other 3D CNNs. Moreover, the results of ablation studies showed a notable improvement in sex determination with the embedding of both MSI and AGAM. Consequently, SDetNet demonstrated automatic and accurate sex determination by learning the anatomical context information of the frontal sinus on CBCT scans.

Personal identification using frontal sinus coding methods: The effect of mixed image modality comparisons.

Several code-based methods have been created for comparing the frontal sinus in skeletal identification scenarios. However, little is known regarding matched-pair accuracy rates of these methods or how varying image modalities may affect these rates. The goals of this study were to validate the exclusion rates and to establish matched-pair accuracy rates of two well-cited coding methods, Cameriere et al. [23] and Tatlisumak et al. [24]. Additionally, individual variables were assessed for consistency in scoring between image modalities. Using a sample of U.S. African American, Native American, and European American females and males (n = 225), we examined individual variable scoring and string codes between two different image modalities (radiographs and CT-based 3D models). Arcades showed poor scoring consistency between modalities (p < 0.001). Although exclusion rates were similar to those reported in the original studies (93%-96%), matched-pair accuracy rates were low (13%-18%). None of the demographics (collection, sex, age, ancestry, and orientation) had an effect on the odds of a match. Interobserver and intraobserver analyses showed moderate to near-perfect agreement for all variables except supraorbital cells, which had minimal to no agreement. Currently, we do not recommend the application of these frontal sinus coding methods independent of other supporting identification methods given low variable consistency and accuracy rates. Visual identification should still be used to include or exclude an identification when using the frontal sinus.

Bilateral sinonasal inverted papillomas originating from both sides of the frontal sinus and the left lamina papyracea: A case report.

RATIONALE: The present investigation documented a case of bilateral sinonasal inverted papilloma (SNIP) that arose from both sides of the frontal sinus and ethmoid sinus. The occurrence of bilateral involvement of the nasal cavities and frontal sinus is rather infrequent. PATIENT CONCERNS: Informed consent was obtained from the patient. DIAGNOSIS: Bilateral SNIP. INTERVENTIONS: The tumor was completely removed by Draf III endoscopic resection complemented by an external eyebrow arch approach, and the postoperative recovery was uneventful. OUTCOMES: The purpose of this paper is to present a comprehensive reference for the management of bilateral SNIP that affects the frontal sinuses. LESSONS: This study addresses the staging and surgical management of bilateral SNIP, along with a review of the factors contributing to its recurrence. The recommended treatment method involves applying the Draf III technique combined with an external nasal approach.

Psammomatoid ossifying fibroma in the frontal sinus: An intriguing clinical encounter-A detailed case report.

BACKGROUND: Psammomatoid ossifying fibroma (POF) is a rare craniofacial neoplasm, primarily affecting the maxillofacial region, and typically observed in adolescents and young adults. This case report presents a unique occurrence of POF in a 50-year-old male, defying the conventional age range and exhibiting an unusual anatomical location within the frontal sinus. CASE: A 50-year-old male with a prior history of cecal adenocarcinoma and colectomy presented with left eye proptosis and new-onset headaches. Imaging revealed a well-defined calcified mass in the left frontal sinus, leading to a diagnosis of POF. Open surgical resection was performed to remove the tumor, and histopathological evaluation confirmed its diagnosis as psammomatoid ossifying fibroma. The patient exhibited no postoperative complications or signs of recurrence. CONCLUSION: This case underscores the diverse clinical presentations and diagnostic challenges associated with POF, emphasizing the importance of accurate diagnosis and multidisciplinary collaboration. Further research is needed to explore the genetic underpinnings and optimal management strategies for this intriguing condition.

Carolyn's window approach for spontaneous frontal sinus meningoencephalocele.

Spontaneous meningoencephaloceles (MECs) are sparsely documented in the literature. Those occurring in the frontal sinus are an exceedingly rare entity. MECs are commonly associated with cerebrospinal fluid (CSF) rhinorrhoea. CSF rhinorrhoea is frequently misdiagnosed, causing delays in diagnosis and management. The subsequently increased risk of bacterial meningitis can be life-threatening to patients. We report the case of a woman in her late 70s with a spontaneous frontal sinus MEC, presenting with a 6-month history of CSF rhinorrhoea. The patient was successfully treated using the novel Carolyn's window approach endoscopically; 9-month follow-up revealed no skull-base breach. Our case emphasises the importance of considering MEC as a differential diagnosis for clear rhinorrhoea and demonstrates successful repair through a novel surgical approach.

Management of frontal sinus fractures requiring surgical intervention: An analysis of a case series.

<b><br>Introduction:</b> Isolated frontal bone fractures constitute 5-15% of traumatic facial fractures cases, with frontal sinus fractures categorized into anterior wall, posterior wall, or complex fractures. The approach is tailored to fracture type and bone fragment displacement. This paper presents the summary of surgical management in patients with isolated and complex fractures of the anterior wall of the frontal sinus.</br> <b><br>Material and Methods:</b> Five patients with different frontal sinus fractures were treated surgically. The same management protocol - diagnosis and surgical intervention was implemented in all cases The retrospective analysis included fracture assessment, surgical approach, and long-term outcomes evaluation.</br> <b><br>Results:</b> The most common cause of fractures was falls, while two complex fractures involved the anterior and posterior walls. External approach, bone fragment removal, endoscopy, and external stabilization were employed in all cases. One patent required delayed revision surgery due to retaining metallic foreign body. Follow-up radiological examinations showed proper healing and cosmetic outcomes were satisfactory in all of the cases.</br> <b><br>Conclusion:</b> Surgical management of isolated fractures of the frontal sinus anterior wall, involving bone fragment removal, realignment, and endoscopy, yielded satisfactory functional and cosmetic outcomes without internal or external stabilization. Long-term monitoring and symptom assessment are crucial, especially in cases with penetrating injuries and foreign body risk.</br>.

Variation, sexual dimorphism, and enlargement of the frontal sinus with age in adult South Africans.

OBJECTIVES: To document frontal sinus volume (FSV) in a sample of sub-Saharan Africans with a view to evaluating claims that such populations exhibit comparatively small sinuses. This study also addresses questions related to sexual dimorphism, incidence of sinus aplasia, and the possibility that FSV continues to increase through adulthood. MATERIALS AND METHODS: FSV was measured from CT scans of adult crania from the Dart Collection. Sex and age were known for each individual. Linear cranial dimensions were used to compute a geometric mean from which a scaled FSV was computed for each cranium. RESULTS: FSV does not differ significantly between sexes, but females exhibit a higher incidence of aplasia. There is considerable variation in FSV in this sample, with the average ranking among the higher means reported for other population samples. The incidence of FS aplasia falls within the range of values recorded for other population samples. Although our study is cross-sectional rather than longitudinal, there is strong evidence that FSV continues to increase with age throughout adulthood. DISCUSSION: The FSV mean of our sample contradicts the notion that sub-Saharan Africans possess small sinuses. In a global context, geography (climate and altitude) does not appear to be related to FSV. The absence of sexual dimorphism in our sample is unexpected, as significant dimorphism has been reported for most other population samples. Our results support other indications that the frontal sinus continues to expand throughout adulthood, especially in females, and that it is likely due to bone resorption.

CT analysis of frontal recess air cell and fluid dynamics simulation of frontal sinus in people with different frontal sinus development after Draf1-3 surgery.

OBJECTIVE: To explore the effects of Draf1-3 on frontal sinus airflow and frontal sinus irrigation in people with different frontal sinus development METHODS: The development of the frontal sinus and the distribution of the frontal recess cells were evaluated by CT scan in 150 adults (300 sides). The airflow changes into the frontal sinus and frontal recess after Draf were analyzed by Fluent software under a steady state and quiet inspiratory state. Nasal irrigation after Draf in adults with well-developed frontal sinus was simulated using 120 mL saline at a rate of 12 mL/s in a position at 45° to observe the changes in transient flow distribution. RESULTS: The moderately developed type of the frontal sinus was the most common. The airflow patterns in the frontal sinus and frontal recess in the moderate development group were laminar, while several large vortexes were formed between the frontal sinus and frontal recess in the well-development group. The Draf exerted more significant effects on the patterns, pressure, and velocity of the airflow in the frontal sinus and frontal recess in the well development group than in the moderate development group. The volume fraction of saline in the frontal sinus increased significantly from Draf1 to Draf3, and the time required for a complete infiltration of saline in the frontal sinus mucosa was significantly reduced. CONCLUSIONS: Draf1-3 has different effects on the airflow field of the frontal sinus with different developmental types; and Draf1-3 can significantly improve the postoperative flushing of the frontal sinus.

The Upper Attachment of the Uncinate Process and Anterior Ethmoidal Artery.

OBJECTIVE: Variations in the upper attachment of the uncinate process (UP) are important because they can affect frontal sinus drainage and change the morphology. Functional endoscopic sinus surgery (FESS) is the primary technique used to treat chronic medically refractory rhinosinusitis. Uncinectomy is the basis of FESS technique to obtain the best possible result from surgery. The anterior ethmoidal artery (AEA) enters the nasal cavity through the orbital medial wall (lamina papyracea) may also be affected by the upper attachment of the UP. The aim of this study was to investigate a possible link between UP variations and the course of the AEA. MATERIALS AND METHODS: This retrospective, computed tomography (CT)-based, anatomic study was conducted on 200 healthy adults (100 females and 100 males) by screening bilateral paranasal sinus images. The upper attachment of the UP was classified in 6 types (1-6) based on the Liu classification. The AEA was divided into 4 types (A-D) based on location: anterior to the frontal sinus (A), between the frontal sinus and the middle nasal turbinate (B), and anterior to the posterior ethmoidal cells (C and D). All the CT images were evaluated simultaneously by 2 anatomists and 1 radiologist. RESULTS: Of the total cases (200 right and 200 left side), 48.8% were type 1 UP attachment, 11.0% type 2, 12% type 3, 9% type 4, 18% type 5, and 1.2% type 6. The AEAs were classified as 12.2% type A, 71.8% type B, 15.2% type C, and 0.8% type D. CONCLUSION: The course of the AEA through the nasal cavity was observed to shift anteriorly from the ethmoidal bulla to the frontal sinus in patients with UP attached to the lamina papyracea and middle turbinate. Remarkably, the AEA always coursed anterior from the middle nasal turbinate line.

Sex estimation of frontal sinus volume from computed tomography scans in a Western Australian adult population.

With the increasing use of radiological three-dimensional imaging, different metric and morphological aspects of the frontal sinuses (FS) have been examined relative to their potential to aid human identification, including sex estimation. The aim of this study is to assess the validity of the metric analysis of the FS volume for estimating sex in a Western Australian (WA) adult population, following the Michel et al. (2015) method. The right, left and total frontal sinus volume (TFSV) from 99 computed tomography scans (47 males and 52 females) of WA individuals aged 18-40 years were three-dimensionally reconstructed using OsiriX® and their volumes acquired in mm3. Sexual dimorphism in the TFSV was tested, and the accuracy of the Michel et al. (2015) formulae was calculated. Population-specific regression equations were also produced. There was a significant difference between the mean TFSV in males and females. The classification accuracy derived from the Michel et al. (2015) formulae was 59.6%. The WA-specific logistic regression analysis yielded an accuracy of 57.2%. The low accuracy rates preclude the use of the sex estimation method in the WA population, but the volume analysis confirmed the individual variability of the frontal sinuses, which may be useful for personal identification.

Anatomical variations of the frontal sinus: A computed tomography-based study.

Background: The pneumatization of the frontal sinus is variable between individuals, including monozygotic twins. The volumetric anatomic variants of the frontal sinus are classified into aplasia, hypoplasia, medium-sized, and hyperplasia. We aimed to study the frontal sinus morphology in Omani patients using computed tomography (CT) evaluations. Methods: Retrospectively, 1220 frontal sinus CT scans from 610 patients investigated at Sultan Qaboos University Hospital, Oman, from January 2019 to December 2020 were reviewed. The frontal sinus morphology was classified according to the classification proposed by Guerram et al. The Chi-square test was used to determine the influence of sex. Results: With regard to the unilateral occurrence, the most prevalent frontal sinus category observed was medium-sized (13.3%), followed by hyperplasia (7.9%), hypoplasia (5.4%), and aplasia (2%) categories. Similarly, in bilateral occurrence, the most common frontal sinus category observed was medium-sized (53%), followed by hyperplasia (13.1%), hypoplasia (3.4%) and aplasia (2%) categories. Right and left frontal sinus aplasia were observed in 2.1% and 1.8% of cases, respectively. In terms of sex influence, the left unilateral ( p<0.01) and the bilateral hypoplasia ( p<0.05) were significantly higher in females. On the other hand, the left unilateral ( p<0.01) and the bilateral hyperplasia ( p<0.05) were higher in males. Conclusions: The baseline data of frontal sinus category frequencies reported in the present study is helpful in the diagnostic evaluation of sinusitis in the clinical setting. The preoperative recognition of frontal sinus types, particularly frontal sinus aplasia in multiplanar CT scans, is crucial to avoid unexpected complications while performing endoscopic sinus surgery.

Frontal trans-sinusal approach: how I do it.

BACKGROUND: Anterior skull base lesions could be reached by different approaches (subfrontal, pterional, interhemispheric, etc.). In selected cases, the frontal trans-sinusal approach is an effective alternative to conventional techniques. METHODS: We present our technique to perform a frontal trans-sinusal approach in a patient affected by a large olfactory groove meningioma. DISCUSSION-CONCLUSION: The frontal trans-sinusal approach allows to approach safely lesions of the median anterior cranial fossa. This approach provides lower brain retraction, easier access to olfactory grooves, and earlier tumor devascularization. However, it remains limited to patients with large-sized frontal sinuses and entails some postoperative risks such as mucocele or CSF leak.

Investigating the link between frontal sinus morphology and craniofacial characteristics with sex: A 3D CBCT study on the South Indian population.

Background: Measurement of craniofacial parameters plays an important role in sex determination in forensic science. The present study was done using cone beam computed tomography (CBCT) scans to evaluate the morphologic structure of the frontal sinuses and compare it with the width of nasal, cranial, maxillary and mandibular width which might help us in sex determination. Methods: A cross-sectional retrospective study was conducted using 142 full field of view (FOV) scans of patients archived from the department. The width of the nose, cranium, maxilla, and mandibular width was measured and compared with the frontal sinus between the two sexes. Results: A paired t-test was done to compare the linear measurements for both sexes' right and left frontal sinuses. The measurements were higher in males when compared to females. There was a statistically significant asymmetry (larger dimension on the left side) of the anterioposterior (p-value of 0.012) and superior-inferior dimensions in males (p-value of 0.135). Spearman's correlation showed that frontal sinus correlated with other craniofacial parameters like nasal, cranial, maxillary and mandibular width among both sexes. The frontal sinus, nasal, cranial, maxillary and mandibular widths were higher in males when compared to females (independent t-test). Discriminant function scores showed 66-68% accuracy to discriminate sex, using the anteroposterior dimension and mandibular width. Conclusions: The measurement of craniofacial parameters using CBCT can aid in determining the sex of unidentified and decomposed bodies.

Computed tomographic characteristics of frontal sinus ossifying fibroma in a dog.

A 10-year-old female spayed Kelpie cross was presented to The Austin Vet Specialists for further investigation of a mineralized, lobulated frontal sinus mass that had previously been detected radiographically. Computed tomography (CT) revealed a large, expansile, well-defined, heterogeneously mineral attenuating mass invading both frontal sinuses. The mass was surgically debulked via a frontal sinusotomy approach. Histopathology was consistent with ossifying fibroma. This  is the first published report to describe frontal sinus ossifying fibroma in a dog, and the second to describe CT features of ossifying fibroma involving the cranium in a dog.

Change of frontal sinus in age of according to the international frontal sinus anatomy classification.

BACKGROUND: The radiological and surgical anatomy of the frontal sinus should be well-known in all age groups to successfully manage frontal sinus diseases and reduce the risk of complications in sinus surgery. PURPOSE: To define frontal sinus and frontal cells according to the International Frontal Sinus Anatomy Classification (IFAC) criteria in pediatrics and adults. MATERIAL AND METHODS: A total of 320 frontal recess regions of 160 individuals (80 pediatric, 80 adults) who underwent a computed tomography (CT) scan of the paranasal sinus (PNS) were included in the study. Agger nasi cells, supra agger cells, supra agger frontal cells, suprabullar cells, suprabullar frontal cells, supraorbital ethmoid cells, and frontal septal cells were evaluated in the CT analysis. RESULTS: The incidence rates of the investigated cells were determined to be 93.1%, 41.9%, 60.0%, 76.3%, 58.5%, 18.8%, and 0% in the pediatric group, respectively, and 86.3%, 35.0%, 44.4%, 54.4%, 46.9%, 19.4%, and 3.4% in the adult group, respectively. Considering the unilateral and bilateral incidence of the cells, agger nasi cells were highly observed bilaterally in both the pediatric group (89.87%) and the adult group (86.48%). CONCLUSION: Our study results show that IFAC can be used as a guide to increase the chance of surgical treatment in the pediatric and adult groups and that the prevalence of frontal cells can be determined radiologically and contributes to the generation of estimations of the prevalence of frontal cells.

Frontal sinus hypoplasia in unoperated older patients with craniosynostosis: a pilot study.

PURPOSE: The purpose of this study is to determine whether patients with unoperated craniosynostosis have different frontal sinus pneumatization than unaffected controls. METHODS: Retrospective review was performed between 2009 and 2020 of previously unoperated patients with craniosynostosis older than 5 years old at first presentation to our institution. Total frontal sinus volume (FSV) was calculated using 3D volume rendering tool in Sectra IDS7 PACS system. Age-matched normative FSV data was collected from 100 normal CT scans for the control group. The two groups were statistically compared using Fisher's exact test and T-test. RESULTS: Study group included nine patients, 5-39 years old, median age 7 years. Frontal sinus pneumatization was absent in 12% of the normal 7-year-old controls, while frontal sinus pneumatization was absent in 89% of the studied craniosynostosis patients (p < .001). Mean FSV of the study group (113 ± 340 mm3) was significantly different from that of age matched control mean FSV (2016 ± 2529 mm3) (p = .027). CONCLUSIONS: Frontal sinus pneumatization is suppressed in unreleased craniosynostosis and may be an intracranial space conservation phenomenon. This absent frontal sinus can have implications in future frontal region trauma and frontal osteotomies.